高分子刷/银纳米粒子复合表面增强拉曼散射基底检测群体感应信号分子  

Fabrication of Polymer Brush/Silver Nanoparticle Nanocomposite as Surface Enhanced Raman Scattering Substrate for Detection of Quorum Sensing Signal Molecule

作　　者：王向东 张倩 褚立强 WANG Xiang-Dong;ZHANG Qian;CHU Li-Qiang(College of Chemical Engineering and Materials Science,Tianjin University of Science&Technology,Tianjin 300457,China)

机构地区：[1]天津科技大学化工与材料学院,天津300457

出　　处：《分析化学》2018年第11期1763-1769,共7页Chinese Journal of Analytical Chemistry

基　　金：教育部新世纪优秀人才支持计划(No.NCET-12-1064)资助~~

摘　　要：利用原子转移自由基聚合技术(ATRP)在硅片上合成聚甲基丙烯酸寡聚乙二醇酯(POEGMA)高分子刷,采用多次浸泡法在高分子刷中固定多层银纳米粒子(Ag NP),形成POEGMA/Ag NP复合SERS基底。扫描电镜和紫外-可见吸收光谱分析表明,纳米粒子成功固定到POEGMA高分子刷中并具有一定的三维排列。利用此SERS基底检测了绿脓杆菌以及两种代表性的QSSM分子(即绿脓素(PCN)和N-十二酰基高丝氨酸内酯(C12-HSL))。实验结果表明,此SERS基底对PCN的检出限为10!10mol/L,C12-HSL的检出限为10!8mol/L,绿脓杆菌的检出限为10 CFU/m L。拉曼测试结果表明,POEGMA/Ag NP纳米复合SERS基底可以对绿脓杆菌和绿脓素进行同时检测和区分。结合SERS技术的免标记、高灵敏性以及受水干扰小等优势,POEGMA/Ag NP纳米复合SERS基底有望用于群体感应现象的研究。Quorum sensing(QS)is a intercellular communication phenomenon among most bacteria which allows bacteria to monitor and respond their local environment and population density by secreting and sensing certain signal molecules.Pseudomonas aeruginosa(PAE)is one of main opportunistic pathogenic bacteria for wound infection and strong resistance to antibiotics because of the formation of biofilm.Recently,some research groups have reported that the formation of PAE biofilm is mainly controlled by QS mechanism,which relies on the release and recognition of specific low molecular weight molecules(so-called quorum sensing signal molecule,QSSM).Therefore,it is desirable to develop a rapid and sensitive method for the detection of both PAE and its corresponding QSSM to improve the cure of wound infections.In this work,poly(oligo(ethylene glycol)methacrylate)(POEGMA)brushes on Si wafer were prepared by atomic transfer radical polymerization technique(ATRP),which were then employed as matrix for the loading of silver nanoparticles(AgNP)by repeating the immersion-rinsing-drying steps,giving rise to a POEGMA/AgNP nanocomposite SERS substrate.Scanning electron microscopy(SEM)and UV-Visible spectroscopy measurements clearly indicated the 3D distribution of AgNPs within the POEGMA brush.The resulting SERS substrates were then used for the detection of PAE and two typical QSSMs:pyocyanin(PCN)and N-dodecanoyl-homoserine lactone(C12-HSL).Raman measurements suggested that the detection limit of the current SERS substrate for PCN,C12-HSL and PAE was 10-10 mol/L,10-8 mol/L and 10 CFU/mL,respectively.Considering the merits associated with SERS technique,such as label-free,highly sensitive and low interference from water,the current POEGMA/AgNP nanocomposite SERS substrate is highly potential for the future investigation of PAE′s quorum sensing phenomenon.

关 键 词：表面增强拉曼散射 群体感应 绿脓杆菌 绿脓素 高分子刷 银纳米粒子 

分 类 号：O657.37[理学—分析化学]